Apple clicks open its newest computer operating system

The latest version of Apple’s home-computer operating system arrived today.

Apple’s OS X version 10.8, which is known commonly as Mountain Lion and has at least 200 new features, costs $19.99 and can be downloaded from Apple’s App Store. One copy can be installed on all Mac computers that are in a home, but the upgrade will be successful only on Macs that run OS X 10.6.8 or that were purchased by mid-2007.

Mountain Lion has a new notification center and a messaging feature. The notification center merges notifications from multiple applications into one panel. Mountain Lion’s messaging feature allows Mountain Lion users to send messages to an iPad, an iPhone or an iPod Touch that use iOS 5 or to another Apple computer that runs Mountain Lion.

Mac owners who upgrade to Mountain Lion and also use Apple’s iCloud program will be able to save data automatically to all iOS-enabled Apple devices.